Seismo-ionospheric anomalies before the 2019 Mirpur earthquake from ionosonde measurements

•The peak plasma ionospheric frequency (foF2) from ionosonde stations located at Islamabad and Sonmiani is analyzed.•The 30 days running median technique to detect the abnormality in foF2 over the epicenter of impending earthquake.•The major reason of these seismo-ionospheric anomalies is the distance between the ionosonde station and epicenter.•The evidence supports that these seismo-ionospheric precursors are probably due to the lithospheric-ionospheric coupling.